using info from an older tutorial with a newer "perfect setup" tutorial

Hi there I followed The Perfect Setup - Ubuntu 6.06 LTS tutorial
and wanted to add in the added features from the other tutorial
"Virtual Users And Domains With Postfix, Courier And MySQL (+ SMTP-AUTH,
Quota, SpamAssassin, ClamAV) ".

Is the information still relivant? Any major changes need to be done?
Dustin